Device and method for remote zeroing of a biological fluid pressure measurement device

A device for measuring pressure providing hydrostatic pressure compensation and remote zeroing, comprising:

• a) a housing including a measuring cavity and a compensation cavity separated by at least a transducer having a sensing face and a compensating face;
• b) a hydrostatic pressure compensation tube adapted to contain fluid and having a first end in pressure communication with the compensating cavity and a second end in pressure communication with atmospheric pressure;
• c) a pressure monitoring tube adapted to contain a fluid and having a proximal end in pressure communication with the measuring cavity and a distal tip exposed to a pressure to be measured at a first elevation;
• d) first valve means in fluid communication with the proximal end of the pressure monitoring tube and with the measuring cavity, for selectively establishing and interrupting pressure communication between the pressure monitoring tube and the sensing face of the transducer;
• e) an adjustable holding device for fixing the second end of the hydrostatic pressure compensation tube at a second elevation;
• f) a closed fluid path for placing the sensing face of the transducer in pressure communication with the compensating face of the transducer;
• and
• g) valved shunt means disposed in the closed fluid path for selectively establishing and interrupting pressure communication between the sensing face of the transducer and the compensating face of the transducer;
• whereby the pressure measurement device may be remotely zeroed by interrupting with the first valve means the pressure communication between the pressure monitoring tube and the sensing face of the transducer and establishing with the valved shunt means pressure communication between the sensing face and the compensating face of the transducer.

A device for measuring pressure with hydrostatic pressure compensation and remote zeroing, comprising:

• a) a transducer having a sensing face and a compensating face;
• b) a hydrostatic pressure compensation tube adapted to contain a fluid and having a first end in pressure communication with the compensating face of the transducer and a second end in pressure communication with atmospheric pressure;
• c) a pressure monitoring tube adapted to contain a fluid and having a proximal end in pressure communication with the sensing face of the transducer and a distal end exposed to a pressure to be measured at an elevation;
• d) first valve means for selectively establishing and interrupting pressure communication between the pressure monitoring tube and the sensing face of the transducer;
• e) an adjustable holding device for fixing the second end of the hydrostatic pressure compensation tube at an elevation substantially the same as the elevation of the distal end of the pressure monitoring tube;
• and
• f) shunt means including a valve means for selectively establishing pressure communication between the sensing face and the compensating face.

A device for measuring pressure with hydrostatic pressure compensation and remote zeroing, comprising:

• a) a manifold comprising an interior portion and a plurality of ports, the interior portion and the ports selectively in fluid communication with each other;
• b) a transducer coupled to the interior portion of the manifold and having a sensing face and a compensating face;
• c) a hydrostatic pressure compensation tube adapted to contain fluid and having a first end in pressure communication with the compensating face of the transducer and a second end in pressure communication with atmospheric pressure;
• d) a pressure monitoring tube adapted to contain a fluid and having a proximal end in pressure communication with the sensing face of the transducer and a distal tip exposed to a pressure to be measured at an elevation;
• e) first valve means for selectively establishing and interrupting pressure communication between the pressure monitoring tube and the sensing face of the transducer;
• f) an adjustable holding device for fixing the second end of the hydrostatic pressure compensation tube at an elevation substantially the same as the elevation of the distal tip of the pressure monitoring tube;
• and
• g) shunt means including a valve means for selectively establishing pressure communication between the sensing face and the compensating face of the transducer.

A method for remotely zeroing a device for measuring fluid pressure with hydrostatic pressure compensation, the device including a transducer for generating an output signal from which a measured pressure value is derived and having a sensing face and a compensating face, the device further including a first valve means for establishing and interrupting pressure communication between the fluid pressure to be measured and the sensing face of the transducer, and a zeroing means for placing the compensating face of the transducer in pressure communication with a pressure substantially equal to a hydrostatic component of a pressure communicated to the sensing face of the transducer, the device further including a closed fluid path between the sensing face and the compensating face of the transducer, the closed fluid path including shunt means including a second valve means for establishing and interrupting pressure communication between the sensing face and the compensating face of the transducer, the method comprising the steps of:

• a) actuating the first valve means to interrupt pressure communication between the sensing face of the transducer and the fluid pressure to be measured;
• b) actuating the second valve means to establish pressure communication between the sensing face and the compensating face of the transducer;
• c) setting the measured pressure value to zero;
• and
• d) actuating the second valve means to interrupt pressure communication between the sensing face and the compensating face of the transducer.

An improved device for measuring internal body fluid pressure, comprising:

• a housing including a transducer having first and second pressure responsive surfaces for generating a signal corresponding to fluid pressure on each face disposed therein;
• a detector means for establishing fluid pressure communication between a body fluid and the first pressure responsive surface and for producing a signal corresponding to a first pressure representing the sum of the body fluid pressure plus a hydrostatic pressure component;
• a calibration means for establishing a second fluid pressure on the second pressure responsive surface corresponding to the hydrostatic pressure component;
• a zeroing means for establishing fluid pressure communication between the first and second pressure responsive surfaces;
• a means for determining a difference between the first pressure and the second pressure;
• and
• a means for displaying the difference calculated.